The Drosophila dopamine 2-like receptor D2R (Dop2R) is required in the blood brain barrier for male courtship

The blood brain barrier (BBB) has the essential function to protect the brain from potentially hazardous molecules while also enabling controlled selective uptake. How these processes and signaling inside BBB cells control neuronal function is an intense area of interest. Signaling in the adult Drosophila BBB is required for normal male courtship behavior and relies on male-specific molecules in the BBB. Here we show that the dopamine receptor D2R is expressed in the BBB and is required in mature males for normal mating behavior. Conditional adult male knockdown of D2R in BBB cells causes courtship defects. The courtship defects observed in genetic D2R mutants can be rescued by expression of normal D2R specifically in the BBB of adult males. Drosophila BBB cells are glial cells. Our findings thus identify a specific glial function for the DR2 receptor and dopamine signaling in the regulation of a complex behavior.

Phamacokinetics of a single oral dose of dihydroartemisinin in Vietnamese healthy volunteers

Pharmacokinetics of a 240 mg single dose of oral dihydroartemisinin (DHA) was investigated in 8 healthy (5 males, 3 females) Vietnamese volunteers. Plasma concentrations were measured by high-performance liquid chromatography with electrochemical detection in the reductive mode. The concentration time profile of DHA was fitted with one-compartment model with a lag time. Pharmacokinetics of DHA is comparable between males and females even when adjusted with dosage. The median (range) values of pooled pharmacokinetics of oral DHA were: t(lag) 0.41 (0.09-0.78) hours, t(1/2z) 0.58 (0.17-1.43) hours, t(max) 1.6 (1.1-2.2) hours, Cmax 466 (128-787) ng/ml. Cmax/dosage 97.7 (27.2-124.6) ng/ml, t(1/2z) 2.0 (1.5-3.4) hours, AUC 1867 (420-3535) ng x h/ml, AUC/dosage 364.3 (89.3-559.7) ng x h/ml/dosage, Cl/f 45.8 (30.0-190.0) ml/min/kg, Vz/f 8.0 (5.5-29.9) l/kg. Interindividual variation was large, the coefficients of variation (CV) were 47.8% and 45.3% respectively to AUC and Cmax. The t(max) of DHA formulation was comparable with that of DHA metabolite of artemisinin derivatives. The t(1/2z) was longer and shorter than that of DHA metabolites of oral formulations of artesunate and artemether, respectively. For monotherapeutic regimen(s) of DHA, dosing frequency of at least twice a day is suggested. Combined regimen(s) of DHA with other potent, long half-life antimalarials may also be an alternative approach.